SmallerDevices MeanSmaller, Multi-TaskingConnectors

By Earl Kneessi, Sales Engineering Manager,
Fischer Connectors

Designing handhelds, wearables, and tomorrow’s smaller medical devices comes with a unique set of
design challenges. Engineers and designers are doing what they can to drive size,
weight, and cost from their devices, and
that means everyone is looking critically at
every component, including connectors.

New technology in connector design is
changing how medical device manufacturers build reliable devices that are smaller
than ever before. One approach we see is
the increased use of small hybrid connectors in medical devices. These connectors
combine signal and data into one small,
dense connector, simplifying the use of the
device. This is particularly helpful when
the patient is responsible for maintenance
of the device on a daily basis. Patients who
are not technologically proficient—and who
are not medical professionals—bring their
own set of challenges and risks to the table,
especially when their own failing health
plays a role. The fewer the connections
and cables that have to be managed, the
lower the risk of an in-home device problem due to user error.

We constantly work with engineers
designing handheld or wearable connector
solutions so they take up less space and
handle a broader range of functions. The
most common is putting power and signal
into one connector, but there are other
combinations, such as power and fluid or
air, specifically in the medical industry,
that play a role as well. Those engineers
report that their end-use customers ask for
simplicity and ease-of-use, and their bosses
try to keep production costs low while still
maintaining safety, reliability, and FDA-lev-el quality standards. It is not a small task to
satisfy everyone.

The trouble is that most engineers don’t
get the chance to review their connector
solutions all that often, especially when
they need to pass FDA trials. Moving from
the older, larger connectors that handle
only signal or power to today’s smaller
multi-tasking connector, which handles
both power and signal, comes with a bit of
a learning curve. Reviewing the connector
and cable assembly needs and possibilities
early in a project can save a lot of heartache later on.

If your connector solution is somethingthat is connected once and then forgottenabout, you have a myriad of solutionsavailable. You will want to minimize thenumber of wires coming out of yourdevice, and make sure the medical pro-fessional or patient can easily handle thesingle connection. But you don’t need toworry a lot about how the connectors feel,or whether they are easy to connect anddisconnect over a period of time. Makesure the signal and power connectionsdon’t create interference, and go as small asyou can go with the connector.

But if the connector solution is mated
and unmated on a daily or more frequent
basis, you do have to take a look closely at
the end use, the end user, and the environment. For instance, an end use in a hospital
surgical environment, where staff is wearing
gloves, is almost certainly going to need
a different solution than a patient in poor
health managing a small external heart device. So here are a few tips to consider when
going to a hybrid connector solution that
multi-tasks in a frequent-use application.

Look closely at the details

• Sure, you know how many contacts you
need. That’s the easy part. But details
become more important as the voltage
and current increases. Compare models
for the exact size of the contact. A

0.5mm contact will carry more power
than a 0.3mm contact. The smaller the
contact, the lower the current it will
pass, if you can run power at all. You
risk an early connector failure if you
try to run too much power through a
contact that is too small to handle it.

• Pin density and configuration itself isimportant. The ideal connector canhave up to 24 pins and performs severalfunctions including transmission ofpower, Ethernet, HDMI, etc., withoutinterference. The cable plays a signif- The Fischer MiniMax is one example of a mixed power/signal connector.